Quality Aspects of Insects as Food-Nutritional, Sensory, and Related Concepts

Extraction and application of lipids from edible insects

Research on new food sources is a worldwide challenge due to the constant increase in the global population. In this scenario, insects and bug based products have been investigated as feasible food alternatives. They are nutritionally healthy and environmentally sustainable. Eating insects (entomophagy) or utilizing their macronutrients in food formulations can efficiently solve the demand for nutritious food. The benefits of insect-based foods are reported in the literature, mainly because they are viable sources of fat (∼38%) and proteins (∼68%). Fats and oils are recognized as essential nutrients in human nutrition, as they provide a concentrated source of energy and act as structural components of cell membranes and signaling pathways. The high levels of fats/oils of edible insects open the perspective in the food industry to be used as ingredients in the enrichment of several products, such as cookies, biscuits, butter, and margarine, among others, thus contributing to consumer acceptance. Insect fat/oil can be obtained using extraction techniques, such as solvent and supercritical CO2 methods. The method depends on the insect species, fat/oil yield, and process costs. Thus, this review aims to provide current information on the consumption, application, and extraction of edible insect oils.

Development of a lexicon for the sensory description of edible insects commercially available in Australia

Sensory lexicons provide an important tool for describing the sensory properties of emerging, unfamiliar foods such as edible insects. This study sought to establish and validate a sensory lexicon for the description and differentiation of edible insects commercially available in Australia and prepared using common preservation and cooking methods (freeze-drying, hot-air drying, roasting, sautéing and deep-frying). Five species were evaluated, including house crickets (Acheta domesticus), yellow mealworm larvae (Tenebrio molitor), king mealworm larvae (Zophobas morio), tyrant ants (Iridomyrmex spp.) and green tree ants (Oecophylla smaragdina). Following generic descriptive sensory analysis methods, a trained panel (n=8) developed a sensory lexicon of 29 aroma and flavour descriptors, and 16 texture descriptors. Vocabulary were then categorised and ordered to generate a sensory wheel. Due to a lack of cross-over in sensory attributes between species, sub-categories of species-specific vocabulary were also generated for each insect. The lexicon enabled sensory profiling of commercially available edible insect samples which revealed large variation in aroma, flavour, and texture attributes due to both species and preparation method. This work provides a platform for development of a globally relevant edible insect sensory lexicon. International collaboration will enable expansion of the lexicon for use with other insect species and preparation methods, insect-derived ingredients (such as insect powder, defatted insect powder and textured insect protein) and in different cultural settings. As the industry grows, the applicability of vocabulary for differentiating within species and between competitive products should also be assessed.

The contribution of commonly consumed edible insects to nutrition security in the Eastern D.R. Congo

Edible insects are perceived as an incredible opportunity to mitigate the major challenge of sustainably producing healthy foods for a growing world population in the face of climate change uncertainties over the coming decade. In this study, we assessed the nutrient composition and sensory properties of Acheta domesticus, Apis mellifera, Gnathocera trivittata, Gryllotalpa africana, Imbrasia epimethea, Imbrasia oyemensis, Locusta migratoria, Macrotermes subhylanus, Nomadacris septemfasciata, Rhyncophorus phoenicis, Ruspolia differens and Rhynchophorus ferrugineus consumed in Eastern D. R. Congo. The investigated edible insects are highly appreciated and nutritious, with proteins (20.67-43.93 g/100 g) and fats (14.53-36.02 g/100 g) being the major macro-nutrients, proving their potential to improve diets through food enrichment. The high potassium (24-386.67 mg/100 g), sodium (152-257.82 mg/100 g), magnesium (32-64 mg/100 g), iron (5.3-16.13 mg/100 g), calcium (25-156.67 mg/100 g) and zinc (11-19.67 mg/100 g) content make the assessed edible insects a useful mineral-containing ingredient for preventing undernutrition in countries which are plagued by micronutrient deficiencies. A scatter plot of matrices and Pearson's correlations between sensory attributes and nutritional composition showed a negative correlation (r = - 0.45) between protein and appearance. While no strong correlation was observed between nutritional attributes and sensory acceptance, a positive correlation was observed between potassium and aroma (r = 0.50), after-taste (r = 0.50) and acceptability (r = 0.52). Principal component analysis results indicated that the two axes accounted for up to 97.4% of the observed variability in the nutrient composition and sensory attributes of commonly consumed edible insects in the Eastern D. R. Congo. Given the significant delicacy and nutritional potential of edible insects highlighted in this paper, households can rely on the latter to meet their nutritional needs rather than conventional livestock, thus contributing to environmental and financial security through local business opportunities.

Selection of host plants for production of Clanis bilineata (Lepidoptera: Sphingidae)

Clanis bilineata Walker (Lepidoptera: Sphingidae), a burgeoning edible insect, is experiencing rising demand in China and other regions. Despite this interest, larval production is currently constrained by the limitations of artificial production technologies, particularly the selection of optimal host plants. This study rigorously evaluated the performance of C. bilineatha larvae on four main host plants: round-leaf soybean, pointed-leaf soybean, black locust, and kudzu. Preference tests demonstrated that the larvae were most attracted to black locust (34.76 ± 4.65%), with subsequent preferences for kudzu (25.00 ± 6.12%), round-leaf soybean (23.17 ± 2.79%), and pointed-leaf soybean (14.02 ± 4.74%). No significant preference differences were noted between round-leaf soybean and either black locust or kudzu. In feeding assays, the larvae exhibited a marked preference for round-leaf soybean (37.36 ± 0.81 g, total feeding amount for larvae), followed by kudzu (37.26 ± 0.82 g), pointed-leaf soybean (35.38 ± 1.31 g), and black locust (28.53 ± 0.81 g). When the larvae were fed on round-leaf soybean, they exhibited significantly higher survival rate (39.33 ± 0.90%), body weight (9.75 ± 0.07 g), total biomass (383.43 ± 7.35 g), pupation rate (87.78 ± 1.73%), and egg production (189.80 ± 1.06 eggs/female) compared to other hosts. These findings uncovered that round-leaf soybean significantly enhances larval performance, suggesting its potential for improving C. bilineata larval production and sustainability in cultivation systems.

Protein and protein-polysaccharide composites-based 3D printing: The properties, roles and opportunities in future functional foods

The food industry is undergoing a significant transformation with the advancement of 3D technology. Researchers in the field are increasingly interested in using protein and protein-polysaccharide composite materials for 3D printing applications. However, maintaining nutritional and sensory properties while guaranteeing printability of these materials is challenging. This review examines the commonly used protein and composite materials in food 3D printing and their roles in printing inks. This review also outlines the essential properties required for 3D printing, including extrudability, appropriate viscoelasticity, thixotropic properties, and gelation properties. Furthermore, it explores the wide range of potential applications for 3D printing technology in novel functional foods such as space food, dysphagia food, kid's food, meat analogue, and other specialized food products.

The Acceptance of Cream Soups with the Addition of Edible Insects (Mealworm, T. molitor; House Cricket, A. domesticus; Buffalo Worm, A. diaperinus; Grasshopper, R. differens) among Young People and Seniors in Poland

Research on the acceptance of consuming insects in one's diet shows the increasing importance of this issue in the context of a sustainable food chain and ecology. Insects represent a promising food source due to their high nutritional value, efficiency in production, and minimal environmental impact, as well as the growing awareness of ecological issues. Despite these benefits, cultural and psychological barriers hinder the acceptance of consuming insects in Western countries. In this study, an assessment was made of the acceptance level of cream-type soups made from tomatoes and white vegetables with the addition of 20% flour from four insect species: mealworm (T. molitor); house cricket (A. domesticus); buffalo worm (A. diaperinus); and grasshopper (R. differens), compared to a control sample. One hundred and four subjects (55 seniors and 49 young adults) participated in this study. The acceptance level of various soups with insect flour was evaluated, considering different sensory parameters such as appearance, smell, taste, and texture. The research showed that older people have a lower acceptance for dishes containing insects compared to young adults, but the differences in the responses given were not statistically significant (p = 0.05), rejecting the assumption that insect-based products should be mainly targeted at young people. Of all the proposed test samples, the mealworm (T. molitor) was the most acceptable insect species in the tests in both taste versions for both age groups. The average score was 6.63 points on a 10-point scale. The products with the addition of grasshopper (R. differens) were rated the lowest. The acceptance level ranged between 4.23 and 4.38 points. A multiple regression analysis showed that taste and texture had the strongest influence on the overall acceptance of these dishes, and the results obtained were highly correlated with the general opinion of the testers. The increasing acceptance level and growing interest in this type of food can be a positive step towards sustainable and efficient food production.

Termites as human foods-A comprehensive review

Global food production is anticipated to rise along with the growth of the global population. As a result, creative solutions must be devised to ensure that everyone has access to nutritious, affordable, and safe food. Consequently, including insects in diets has the potential to improve global food and nutrition security. This paper aims to share recent findings by covering edible termites as the main aspect, from their consumption record until consumer acceptance. A total of 53 termite species are reported as edible ones and distributed in 6 biogeographic realms. Generally, termites have a nutrient composition that is suitable for human consumption, and cooked termites are a better dietary choice than their raw counterparts. Besides, increasing customer interest in eating termite-based food can be achieved by making it more palatable and tastier through various cooking processes, that is, boiling, frying, grilling, roasting, smoking, and sun-drying. Moreover, edible termites can also be used as a new source of medication by exhibiting antimicrobial activity. Regarding their advantages, it is strongly encouraged to implement a seminatural rearing system to sustain the supply of edible termites. Overall, this paper makes it evident that termites are an important natural resource for food or medicine. Hence, the long-term objective is to stimulate scientific inquiry into the potential of edible insects as an answer to the problem of global food security.

Liking and Description of Pasta Sauces with Varying Mealworm Content

Entomophagy is directly connected with culture, explaining why it is commonly rejected in Western countries. Due to increased meat consumption in recent years with its associated negative impacts on health and sustainability, the development of products based on alternative protein sources has become urgent. The larval form of Tenebrio molitor (mealworm) has the potential to substitute meat as it requires less resources and produces less emissions compared to other forms of meat production. Therefore, in this project we have aimed to develop pasta sauces with differing mealworm contents based on a common meat sauce and to test the acceptance with 91 consumers in Austria. Three sauces (100% mealworm, 50% mealworm and 50% meat, 100% meat) were developed and tested using a 9-point hedonic scale for acceptance, and the CATA (Check-All-That-Apply) method was integrated to also receive descriptive information. The analysis of the liking data revealed that the liking for the hybrid sauce with meat and mealworm content was comparable to the meat sauce (6.9 ± 1.8. vs. 6.5 ± 1.8, p > 0.05). Less liked was the sauce with the highest mealworm content (5.7 ± 1.8, p < 0.05). The CATA analysis demonstrated the strongest positive effects on the mean in terms of how much the products were liked for the attribute "fleshy" (0.8). On the other hand, the attributes "brownish" (-0.9) or "mushy" (-1.0) had the strongest negative effects on the mean of the liking of products. We have seen that meat cannot be substituted by mealworm immediately and completely. The results suggest a stepwise substitution and the further adaptation of products regarding the (negative and positive effecting) attributes to increase consumer acceptance.

Melon seed: A nutritionally valuable by-product and its effects on cake quality

Incorporating by-products and waste materials with nutritional and industrial potential into food formulations is an important consideration. Melon seeds, known for their nutritious compounds, are often treated as waste. This study aimed to improve the nutritional properties of cakes by adding melon seed flour (MSF), which contains high levels of ash, lipid, protein, and fiber, as a substitute for whole wheat flour and fat at concentrations of 40% and 60%. The primary fatty acid identified was linoleic acid, while the dominant amino acid in the samples was glutamic acid, followed by proline and leucine. It is noteworthy that potassium and magnesium content in MSF was about five times higher than control. The substitution of MSF did not cause a significant change in the structural properties of the cakes but led to a decrease in the firmness, springiness, and chewiness. Consumer acceptance, based on sensory evaluation, indicated that cakes with 40% MSF substitution were well-received. In conclusion, our findings demonstrate that melon seeds, previously considered waste, can serve as a good alternative source of fiber, fat, and protein in bakery products.

The Use of Gonimbrasia belina (Westwood, 1849) and Cirina forda (Westwood, 1849) Caterpillars (Lepidoptera: Sarturniidae) as Food Sources and Income Generators in Africa

Gonimbrasia belina (mopane worm) and Cirina forda caterpillars (Lepidoptera: Saturniidae) are mostly found in shrubs and trees, from where they are collected as larvae and are widely consumed across southern Africa by rural and increasingly urban populations. These caterpillars are among the most prominent, traded, and economically beneficial edible insects found in Western African countries, but also in South Africa, Zimbabwe, Botswana, and the Democratic Republic of the Congo. Over the years, these caterpillars have evolved from being part of the diet in various communities to playing a vital role in income generation. In addition, consumption of G. belina and C. forda caterpillars as potential food sources has gained momentum due to their potential for contributing to livelihoods and mitigating food security challenges across Africa while providing significant benefits to developing countries on a socio-economic and ecological level. Edible caterpillars serve as a good source of rich nutrients such as proteins, fatty acids, and micronutrients and can be used in formulating nutrient-dense complementary foods. However, limited information is available, specifically on different trees that serve as hosts to these caterpillars, as they depend on the leaves as their only source of food. In addition, the review aims to critique and document knowledge on the nutritional benefits, acceptance of the use of these caterpillars as food security, commercial value, and level of acceptance towards the utilization of caterpillars as food sources.

Alternative Protein Sources and Novel Foods: Benefits, Food Applications and Safety Issues

The increasing size of the human population and the shortage of highly valuable proteinaceous ingredients has prompted the international community to scout for new, sustainable, and natural protein resources from invertebrates (e.g., insects) and underutilized legume crops, unexploited terrestrial and aquatic weeds, and fungi. Insect proteins are known for their nutritional value, being rich in proteins with a good balance of essential amino acids and being a valuable source of essential fatty acids and trace elements. Unconventional legume crops were found rich in nutritional, phytochemical, and therapeutic properties, showing excellent abilities to survive extreme environmental conditions. This review evaluates the recent state of underutilized legume crops, aquatic weeds, fungi, and insects intended as alternative protein sources, from ingredient production to their incorporation in food products, including their food formulations and the functional characteristics of alternative plant-based proteins and edible insect proteins as novel foods. Emphasis is also placed on safety issues due to the presence of anti-nutritional factors and allergenic proteins in insects and/or underutilized legumes. The functional and biological activities of protein hydrolysates from different protein sources are reviewed, along with bioactive peptides displaying antihypertensive, antioxidant, antidiabetic, and/or antimicrobial activity. Due to the healthy properties of these foods for the high abundance of bioactive peptides and phytochemicals, more consumers are expected to turn to vegetarianism or veganism in the future, and the increasing demand for such products will be a challenge for the future.

Recent Insight on Edible Insect Protein: Extraction, Functional Properties, Allergenicity, Bioactivity, and Applications

Due to the recent increase in the human population and the associated shortage of protein resources, it is necessary to find new, sustainable, and natural protein resources from invertebrates (such as insects) and underutilized plants. In most cases, compared to plants (e.g., grains and legumes) and animals (e.g., fish, beef, chicken, lamb, and pork), insect proteins are high in quality in terms of their nutritional value, total protein content, and essential amino acid composition. This review evaluates the recent state of insects as an alternative protein source from production to application; more specifically, it introduces in detail the latest advances in the protein extraction process. As an alternative source of protein in food formulations, the functional characteristics of edible insect protein are comprehensively presented, and the risk of allergy associated with insect protein is also discussed. The biological activity of protein hydrolyzates from different species of insects (Bombyx mori, Hermetia illucens, Acheta domesticus, Tenebrio molitor) are also reviewed, and the hydrolysates (bioactive peptides) are found to have either antihypertensive, antioxidant, antidiabetic, and antimicrobial activity. Finally, the use of edible insect protein in various food applications is presented.

Consumer acceptance of new food trends resulting from the fourth industrial revolution technologies: A narrative review of literature and future perspectives

The growing consumer awareness of climate change and the resulting food sustainability issues have led to an increasing adoption of several emerging food trends. Some of these trends have been strengthened by the emergence of the fourth industrial revolution (or Industry 4.0), and its innovations and technologies that have fundamentally reshaped and transformed current strategies and prospects for food production and consumption patterns. In this review a general overview of the industrial revolutions through a food perspective will be provided. Then, the current knowledge base regarding consumer acceptance of eight traditional animal-proteins alternatives (e.g., plant-based foods and insects) and more recent trends (e.g., cell-cultured meat and 3D-printed foods) will be updated. A special focus will be given to the impact of digital technologies and other food Industry 4.0 innovations on the shift toward greener, healthier, and more sustainable diets. Emerging food trends have promising potential to promote nutritious and sustainable alternatives to animal-based products. This literature narrative review showed that plant-based foods are the largest portion of alternative proteins but intensive research is being done with other sources (notably the insects and cell-cultured animal products). Recent technological advances are likely to have significant roles in enhancing sensory and nutritional properties, improving consumer perception of these emerging foods. Thus, consumer acceptance and consumption of new foods are predicted to continue growing, although more effort should be made to make these food products more convenient, nutritious, and affordable, and to market them to consumers positively emphasizing their safety and benefits.

Mytilicola orientalis

Neozoa are invasive species that enter faunal communities as new species. Not infrequently, they pose a threat to local ecosystems. Climate change could further promote these developments or favor neozoa. Thus, they represent a relevant threat in the future. One of these neozoa is the copepod parasite Mytilicola orientalis. This parasite originates from Asia and infects a wide variety of bivalves like mussels and oysters. However, as an invasive species, it can be found more and more frequently in Europe, especially in the North and Baltic Seas. There, M. orientalis poses a real threat to mussels in aquaculture and thus also to the local economy.

Edible Insects in Latin America: A Sustainable Alternative for Our Food Security

Nowadays, the food industry faces paramount challenges in different areas, since worldwide consumers are increasing every day, and at the same time, they are demanding new convenient products. Recent studies show that the current food production system is unsustainable over time and therefore is necessary to create new alternatives of production. New food trends are focused on the consumption of natural products, that have an eco-friendly production approach, and a beneficial nutritional profile for the consumer’s health. Hence, products are being created to not only have good organoleptic characteristics, but also to contain a wide variety of micro and macronutrients, and to be sustainable within their production. For this reason, the use of raw materials that satisfy the needs previously mentioned is being implemented. For instance, the use of insects as raw material, because they have a high protein content comparable to animal-based foods. Specifically, ants and crickets can contain between 9 and 77% protein of dry weight, while beef contains between 25 and 28%. On the other hand, insects present an ease and sustainable production system, compared to livestock farming, since some of them feed with food waste generated by humans. In addition, require less food for their upbringing; insects can convert 2 kg of feed into 1 kg of insect mass, while cattle use 8 kg of feed to produce 1 kg of body weight. On the other hand, there is evidence that insects produce fewer greenhouse gases during their production, for example, pigs produce between 10 and 100 times more greenhouse gases per kg of weight. United States, Mexico, Chile, Peru, and Argentina have begun to develop and consume these products; thus, promoting different and new ventures. Large-scale production of insect-based food products could help solve or even prevent the looming food problem and contribute to the sustainable development goals set by the United Nations. Thus, the aim of this review work was to compile and investigate the edible insect’s alternatives in Latin America, as well as the commercially available or potential derivative products. We discussed the nutritional value of edible insects, and how they could contribute to food security.

Edible insects, a valuable protein source from ancient to modern times

The current COVID-19 pandemic has demonstrated that we are not prepared to deal with food security amid unexpected situations; the FAO (Food and Agriculture Organization) has stipulated that the future of our food & agriculture looks challenging toward the year 2050; primarily in response to the fact that global population is expected to increase by 9 billion people by 2050. Although entomophagy has been practiced by humans for thousands of years, until recently, edible insects have gained special attention due to their high nutritional value (particularly their high protein and essential amino acid content) and lower environmental impact that could help alleviate the global food demand. Edible insects are classified into eight main orders belonging to Blattodea (cockroaches and termites), Coleoptera (beetles), Diptera (flies), Hemiptera (cicadas, stink bugs), Hymenoptera (bees, wasps, ants), Lepidoptera (butterflies, moths), Odonata (dragonflies), and Orthoptera (crickets, grasshoppers, locusts). Several traditional cooking (e.g., boiling, roasting, sun-drying) and processing technologies (e.g., pasteurization, enzymatic proteolysis, high pressure processing) have shown that it is feasible to prepare safe and nutritious insects and/or foods with insects. Nevertheless, challenges associated with consumers acceptance to eat insects, as well as potential presence of anti-nutritive factors and allergens, need to be carefully evaluated as the industry grows in the coming years. Foreseeing such food shortages during pandemics and future food security concerns, consumers, scientists, and the food industry need to consider the value of farming insects as promising protein sources.

Nutritional Properties of Larval Epidermis and Meat of the Edible Insect Clanis bilineata tsingtauica (Lepidoptera: Sphingidae)

Insects represent a sustainable, protein-rich food source widely consumed in Asia, Africa, and South America. Eating Clanis bilineata tsingtauica Mell is common in the eastern part of China. A comparative characterization of nutrients in the meat and epidermis of C. bilineata tsingtauica was performed in this study. The results showed this insect to be high in nutrients, particularly in the epidermis where protein total was 71.82%. Sixteen different amino acids were quantified in C. bilineata tsingtauica, and the ratio of essential to nonessential amino acids in the epidermis and meat was 68.14% and 59.27%, respectively. The amino acid composition of C. bilineata tsingtauica is balanced, representing a high-quality protein source. Eight minerals were quantified in C. bilineata tsingtauica, including four macro and four trace elements. Fe in the epidermis and Zn in the meat were abundant at 163.82 and 299.31 μg/g DW, respectively. The presence of phytic acid impacted the absorption of mineral elements in food. We also detected phytic acid in C. bilineata tsingtauica. The molar ratio of phytic acid to zinc (PA/Zn) in C. bilineata tsingtauica was very low (3.28) compared to Glycine max and Cryptotympana atrata, which indicated that mineral utilization was high. In conclusion, this study confirms that C. bilineata tsingtauica is a highly nutritious food source for human consumption, and the results provide a basis for further consumption and industrialization of this edible insect.

Insects as an Alternative Protein Source

The recent COVID-19 pandemic drastically affected food supply chains worldwide, showing the vulnerability of food security. Efforts to develop alternative protein sources that are sustainable and can help alleviate global food shortage problems should be prioritized. Insects have been part of our diet for thousands of years and still are today, and market trends show a global increase in the number of food-grade insect producers. The global market for edible insects has been forecasted to reach US$8 billion by the year 2030. Insects are highly nutritious and have bioactive peptides with potential therapeutic effects. This review provides an overview of the consumption of insects from ancient to modern times, discusses the rationale for using insects as alternative protein sources, and presents a summary of the major insects consumed worldwide as well as a brief description of the traditional and novel technologies currently used to process insects and/or extract their nutritional components. Expected final online publication date for the Annual Review of Food Science and Technology, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

The effect of yellow mealworm larvae meal supplementation in broiler diets on meat quality

The aim of this study was to evaluate the effect of Tenebrio molitor larvae meal supplementation in chicken diets on the chemical composition and sensory quality of meat. The experiment was conducted on 120 Ross 308 male broilers from day 12 to day 38 of their age. Broilers were divided into three equal groups with 5 replicates per treatment. The two experimental groups received feed mixtures containing 2% (TM2; n = 40) and 5% (TM5; n = 40), respectively of yellow mealworm (Tenebrio molitor L.) meal. The third group (TM0; n = 40) was control, receiving 0% of mealworms in diet. The addition of mealworm meal to diets in this trial do not worsen the chemical composition or sensory characteristics of the thigh meat of broilers. The control chickens had a higher live weight (P < 0.05) compared to the experimental groups at the end of the trial. The lowest live weight and feed intake was determined in group TM2 (P < 0.05). The highest feed intake (P < 0.05) was found in the control group. The breast meat from the control group was rated better (P < 0.05) in flavour compared to the groups receiving 2% and 5% of yellow mealworms. The primary requirement for the use of any ingredient in feed is that it does not adversely affect food safety and quality. In our study, the inclusion of 2% and 5% mealworm meal in the broiler’s diet had no influence on meat quality.

Thermal processing of insect allergens and IgE cross-recognition in Italian patients allergic to shrimp, house dust mite and mealworm

Edible insects are considered as a promising and sustainable alternative protein source for humans, although risk assessments, with particular reference to the allergic potential of insect proteins, are required. Considering that insects are likely to be consumed after processing, it is crucial to assess how processing can influence allergenicity. In our study, we investigated how boiling and frying affect the IgE cross-recognition of proteins from five edible insects (mealworm, buffalo worm, silkworm, cricket and grasshopper). We considered three groups of Italian patients allergic to shrimps and to house dust mites, who had never consumed insects before and two subjects with occupational allergy and food sensitization to mealworm. Our data suggest that thermal processing may change the solubility of proteins, thereby resulting in a protein shift from water-soluble fractions to water-insoluble fractions. Immunoblot and LC-MS/MS analyses have shown that tropomyosin may play an important role as a cross-allergen for house dust mite and shrimp allergic patients, while larval cuticle protein seems to play a major role in the cross-reactivity of patients primarily sensitized to mealworm. On the basis of our results, the effects of processing appear to be protein-, species- and treatment-specific. Therefore, house dust mite, shrimp and mealworm allergic patients should consume insects with caution, even after thermal processing.

Nutritional Composition of Honey Bee Drones of Two Subspecies Relative to Their Pupal Developmental Stages

Simple Summary

Despite the use of honey bee brood as food among several communities of the world, the nutritional potential of drones remained unexplored for a long time. In the recent past some scientific endeavour, including our own previous work, has been undertaken to explore the nutrient quality of this food source. Due to their limited socio-biological role, honey bee drones would be a suitable candidate to compare their nutrient content with that of worker honey bees. We therefore investigated the nutrient composition of honey bee drones belonging to two subspecies, namely Apis mellifera carnica and A. m. mellifera covering their pupal developmental period. To possess information of the drones’ nutritional value during their development would help in choosing the most suitable developmental stage for the commercial production of drone brood as food.

Abstract

We examined the contents of nutritional importance, i.e., amino acids, fatty acids and minerals of different developmental stages of drones of two honey bee subspecies, namely Apis mellifera carnica and A. m. mellifera. The results revealed that, in general, individual amino acid amounts and therefore the total protein increased along with the developmental stages of the drones. No statistically significant differences were found between the same developmental stages of the two subspecies. The reverse, i.e., a decrease with developmental stage occurred in relation to the fatty acid composition. Most of the minerals were higher at advanced developmental stages. Overall, the high protein content (31.4–43.4%), small amount of fat (9.5–11.5%) and abundance of minerals such asiron and zinc, make drones a suitable nutritional resource. Even though nutrient content, especially protein, was higher in the pupae than the prepupae, we propose prepupae also as a commercial product based on their higher biomass production. Provided standard production protocols maintaining hygiene and safety will be adhered to, we propose that drone honey bees can be utilized as human food or animal feed.

Partial Substitution of Meat with Insect (Alphitobius diaperinus) in a Carnivore Diet Changes the Gut Microbiome and Metabolome of Healthy Rats

Insects are suggested as a sustainable protein source of high nutritional quality, but the effects of insect ingestion on processes in the gastrointestinal tract and gut microbiota (GM) remain to be established. We examined the effects of partial substitution of meat with insect protein (Alphitobius diaperinus) in a four-week dietary intervention in a healthy rat model (n = 30). GM composition was characterized using' 16S rRNA gene amplicon profiling while the metabolomes of stomach, small intestine, and colon content, feces and blood were investigated by 1H-NMR spectroscopy. Metabolomics analyses revealed a larger escape of protein residues into the colon and a different microbial metabolization pattern of aromatic amino acids when partly substituting pork with insect. Both for rats fed a pork diet and rats fed a diet with partial replacement of pork with insect, the GM was dominated by Lactobacillus, Clostridium cluster XI and Akkermansia. However, Bray-Curtis dissimilarity metrics were different when insects were included in the diet. Introduction of insects in a common Western omnivore diet alters the gut microbiome diversity with consequences for endogenous metabolism. This finding highlights the importance of assessing gastrointestinal tract effects when evaluating new protein sources as meat replacements.

Effect of Cooking Techniques on the in vitro Protein Digestibility, Fatty Acid Profile, and Oxidative Status of Mealworms (Tenebrio molitor)

Tenebrio molitor (T. molitor) (mealworm) larvae are one of the most promising insects for feed–food purposes. Mealworms are rich in several macro and micro nutritional elements and can be practically reared on side stream substrates. In this study, the effects of seven different cooking techniques were tested on the nutritional value of mealworms focusing the attention on protein digestibility, fatty acid (FA) profile, and oxidative status. Uncooked larvae (UC) were used as control and compared to two combinations of temperature/time in oven cooking (70°C for 30 min, OC70-30, 150°C for 10 min, OC150-10), two methods of frying (mealworms fried in sunflower oil as deep fry, DF, or pan fry, PF), microwaving (MW), boiling (in plastic bag under vacuum, BO), and steaming (ST). Proximate composition, in vitro digestibility (gastric and duodenal), FA profile, and oxidative status (tocopherol and tocotrienol, carbonyl, and lipid oxidation) were then tested. Cooking technique affected all the tested parameters. As expected, cooking affected proximate composition in relation to the method applied (dry matter increased after oven cooking and frying; lipids increased by frying). In vitro digestion revealed the highest value for the OC70-30 method, followed by UC and ST. Deep frying revealed the worst digestibility percentage. FA profile was deeply affected by the cooking technique, with general decrease in SFA and MUFA. The highest modifications in FA profile were revealed in ST larvae with an increased percentage of linoleic acid linked to the lowering of SFA and MUFA contents. Furthermore, deep frying larvae in sunflower oil increased the relative abundance of PUFAs. Tocols values were higher in DF and MW groups than PF (about 6-fold more) and all other groups (7-fold more). Carbonyls increased with oven cooking (OC150-10 and OC70-30), whereas the values were lower with frying and similar to ST and UC. Lipid oxidation was highest as well in OC150-10 but similar to frying methods (DF and PF). Based on the obtained results, it can be concluded that mealworm larvae surely meet human nutritional requirements, but the cooking method must be carefully chosen to maintain a high nutritional value.

Edible Insects: Preliminary Study about Perceptions, Attitudes, and Knowledge on a Sample of Portuguese Citizens

This study investigated the knowledge, attitudes, consumption habits, and degree of acceptability of edible insects (EI) or derived products among Portuguese consumers. This work consisted of a questionnaire survey, undertaken on a sample of 213 participants. For the treatment of data, basic descriptive statistics were used, complemented with chi-square tests to assess some associations between categorical variables. Moreover, a tree classification analysis was carried out using a classification and regression tree (CRT) algorithm with cross-validation. The results indicated that people tend to have correct perceptions about the sustainability issues associated with the use of insects as alternative sources of protein; however, the level of knowledge and overall perception about their nutritive value is low. Regarding the consumption of EI, it was found that only a small part of the participants had already eaten them, doing it mostly abroad, by self-initiative, in a restaurant or at a party or event. Additionally, it was found that the reluctance to consume insects is higher if they are whole, but when they are transformed into ingredients used in food formulations, the level of acceptance increases. Furthermore, men have shown to have a better perception about EI, be more informed about sustainability, and have a higher level of acceptability when compared to women. As a final conclusion, it was observed that the Portuguese still show some resistance to adhere to the use of insects as replacements for meat products, but the market of insect based products can be a good alternative to overpass the neophobia associated with this type of food.

Sensory evaluation and acceptance of food made of edible insects

This paper discusses the sensory analysis of food enriched with selected edible insect species which are labelled as a novel food – house cricket (Acheta domesticus) and mealworm (Tenebrio molitor). Energy bars of two different compositions with the addition of cricket flour and puff pastry bars sprinkled with the whole roasted mealworm larvae were evaluated by consumer tests performed via a questionnaire survey. Respondents represented both men and women in equal numbers and included consumers with the experience of the sensory analysis and edible insects to ensure accurate results. Sensory analyses revealed that respondents associated their tastes with already known flavors (salty, sweet, bitter, fish, French fries, chicken, and mushrooms). The most common answer from respondents was a salty taste, followed by a sweet taste. There were also unusual comparisons such as pine seeds. Consumers’ positive attitude to these energy bars has been registered which shows that the Czech consumer accepts edible insects in a suitable form as a novel food and possible part of the food basket.

Status of meat alternatives and their potential role in the future meat market - A review

Plant-based meat analogues, edible insects, and cultured meat are promising major meat alternatives that can be used as protein sources in the future. It is also believed that the importance of meat alternatives will continue to increase because of concerns on limited sustainability of the traditional meat production system. The meat alternatives are expected to have different roles based on their different benefits and limitations. Plant-based meat analogues and edible insects can replace traditional meat as a good protein source from the perspective of nutritional value. Furthermore, plant-based meat can be made available to a wide range of consumers (e.g., as vegetarian or halal food products). However, despite ongoing technical developments, their palatability, including appearance, flavor, and texture, is still different from the consumers' standard established from livestock-based traditional meat. Meanwhile, cultured meat is the only method to produce actual animal muscle-based meat; therefore, the final product is more meat-like compared to other meat analogues. However, technical difficulties, especially in mass production and cost, remain before it can be commercialized. Nevertheless, these meat alternatives can be a part of our future protein sources while maintaining a complementary relationship with traditional meat.

Chemistry and Sensory Characterization of a Bakery Product Prepared with Oils from African Edible Insects

Globally, there is growing interest to integrate insect-derived ingredients into food products. Knowledge of consumer perception to these food products is growing rapidly in the literature, but similar knowledge on the use of oils from African edible insects remains to be established. In this study, we (1) compared the chemistry of the oils from two commonly consumed grasshoppers, the desert locust Schistocerca gregaria and the African bush-cricket Ruspolia differens with those of olive and sesame oils; (2) compared the proximate composition of a baked product (cookie) prepared from the oils; (3) identified the potential volatiles and fatty acids contributing to the aroma and taste; and (4) examined acceptance and willingness to pay (WTP) for the baked product among consumers with no previous experience of entomophagy. Our results showed that the insect oils were compositionally richer in omega-3 fatty acids, flavonoids, and vitamin E than the plant oils. Proximate analysis and volatile chemistry revealed that differences in aroma and taste of the cookies were associated with their sources of oils. Consumers' acceptance was high for cookies prepared with R. differens (95%) and sesame (89%) oils compared to those with olive and S. gregaria oils. Notably, cookies prepared with insect oils had more than 50% dislike in aroma and taste. Consumers' willingness to pay for cookies prepared with insect oils was 6-8 times higher than for cookies containing olive oil, but 3-4 times lower than cookies containing sesame oil. Our findings show that integrating edible insect oils into cookies, entices people to ''take the first step" in entomophagy by decreasing insect-based food products neophobia, thereby, contributing to consumers' acceptance of the baked products. However, future research should explore the use of refined or flavored insect oils for bakery products to reduce off-flavors that might have been perceived in the formulated food products.

Product Quality during the Storage of Foods with Insects as an Ingredient: Impact of Particle Size, Antioxidant, Oil Content and Salt Content

To increase the acceptability of insects as food in Western culture, it is essential to develop attractive, high-quality food products. Higher acceptability of insect-based food has been shown if the insects are “invisible”. Mincing or chopping the insect material could be a first processing step to reduce the visibility of the insects. In this work, we processed yellow mealworms by using traditional food techniques: chopping, mixing and heat treatment in a retort. The results show that all factors in the experimental design (particle size, oil content, salt content and antioxidant) influenced the products to a larger extent than the storage time. The results, measured by sensory analysis, TBAR values (Thiobarbituric acid reactive substances), colourimetry and viscosity, show clearly that the food products packaged in TRC (Tetra recart cartons) 200 packages and processed in a retort stayed stable during a storage time of 6 months at room temperature.

Contributions of protein and milled chitin extracted from domestic cricket powder to emulsion stabilization

Interfacial and emulsifying properties of fractionated cricket powder were assessed to identify whether emulsification properties originate from protein or chitin particles. Fractions extracted in alkaline water, containing high protein and mineral contents, increased the surface pressure of heptane-water interfaces with near-saturation equilibrium surface pressure of 31 mN/m. Dynamic surface pressure profiles indicated adsorption of protein clusters to the interface. Emulsification capacity of protein fraction was 50% greater than that of the source cricket flour, although oil-in-water emulsions prepared with 1-2% (w/w) protein fraction formed a cream layer within one day of storage. Emulsified layers persisted for up to 20 days, and light scattering measurements described a stable population with surface-volume-mean diameter of approximately 3 μm. Chitin-rich fractions milled to a particle size of 0.5-200 μm contributed negligible surface pressure, and its emulsification capacity was 5% of the value for the source cricket flour. Emulsions prepared with chitin-rich fractions coexisted with an unstable precipitate layer comprising 60% of the added solid, which was attributed to larger particles with poor emulsifying capability. Stable chitin-stabilized emulsion phases were resistant to creaming, yet volume-mean droplet diameter surpassed 50 μm within 24 h of storage. Both protein and chitin fractions have emulsifying capabilities but would require further processing or secondary additives to achieve desirable storage stability.

Entomophagy: Nutritional, ecological, safety and legislation aspects

Globally, there is a need to seek alternative sources of protein in addition to meat. This has led to considerable interest in edible insects. Such insects form part of cultures and diets in many Asian and African countries, and are an excellent source of essential nutrients, minerals, vitamins and proteins. Furthermore, they have been reported to be sustainable. The ecological importance of insects is related to their short life cycles when reared and farmed. This makes them ideal in mitigating greenhouse gas emissions, cutting land uses and polluted water, and reducing environmental contamination. However, the use of edible insects as food in Europe is minimal. To ensure safety of insects when eaten as food, considerations should be made on: microbiological contamination; toxicological hazards, e.g. chemical hazards and antinutrients; allergenicity issues that are related to different exposures, including injection, ingestion, inhalation and skin contact. In this review, we summarize the nutritional and sustainable values of edible insects, look at safety and legislative measures and we finally discuss future issues.

Mealworms as Food Ingredient-Sensory Investigation of a Model System

The use of insects as food is a sustainable alternative to meat and as a protein source is fully comparable to meat, fish and soybeans. The next step is to make insects available for use in the more widespread production of food and meals. Sensory attributes are of great importance in being able to increase the understanding of insects as an ingredient in cooking and production. In this pilot study, mealworms were used as the main ingredient in a model system, where the aim was to evaluate the impact on sensory properties of changing particle size, oil/water ratio and salt content of the insects using a factorial design. Twelve different samples were produced according to the factorial design. Further, the effect of adding an antioxidant agent was evaluated. Sensory analysis and instrumental analyses were performed on the samples. Particle size significantly influenced the sensory attributes appearance, odor, taste and texture, but not flavor, whereas salt content affected taste and flavor. The viscosity was affected by the particle size and instrumentally measured color was affected by particle size and oil content. The addition of the antioxidant agent decreased the changes in color, rancidity and separation.